Method and apparatus for blasting



June 30, 1925.

G. c. LEWIS METHOD AND APPARATUS FOR BLASTINIG Filed July 9, i925 INVENTOR Patented June 3Q, 15.

GEORGE CHARLES LEWIS, OF NEW DORP, N YORK, ASSIGNOR T0 OOLUMBIAN CARP BON' COMPANY, 01 WILLIAMSPORT, PMNSYLVANIA, A CORPORATION O]? DELA- WARE.

METHOD AND APPATUS FOR BLASTING.

Application filed July 9,

To all whom it may co'noem:

Be it known that I, GEORGE G. Lewis, a subject of the King of England, and resident of New Dorp, in the county of Richmond and State of New York, have invented certain new i and useful Improvements in Methods and Apparatus for Blasting, of which the following is a specification.

This invention relates to cartridges for andv methods of blasting in which there is employed a rapidly combustible substance in a finely subdivided state, in the form of a cartridge or package which in itself is not explosive, but which is dipped in the liquid oxygen -or liquid air just before being inserted in a hole in the rock or other body to be blasted. It is there ignited by a time fuse, detonating cap, or other suitable device.

The liquid oxygen is very volatile and the cartridge rapidly loses its efliciency due to this evaporation.

One object of my invention is to retard this evaporation of the oxygen from the cartridge and thus increase the force of the explosion by insuring the presence of sufficient oxygen to produce as near as possible complete combustion, and also ermit longer fuses to give a greater length 0 time for the men to get away from the point where the explosion is to take place after placing and before ignition.

Further objects of my invention are to secure an increased concentration of the liquid oxygen in the center of the cartridge so as to better facilitate the combustion of such inner parts, to provide a reservoir from which the oxygen may pass to the outer parts of the cartridge to make up for loss through evaporation from said outer parts, and to facilitate the rapid saturation of'the cartridge when it is dipped in the liquid oxygen.

In carrying out the first named object of my invention I provide the cartridge with two separate envelopes or jackets, the-inner one of which is permeable to liquid oxygen, and the outer one of which is ve much less permeable and preferably substantially non-permeable except at an outlet end. The inner envelope or container may .be of ordinary paper, while the outerenvelope or container is preferably paper coated with paraffin or otherwise treated to be non- 1928. Serial No. 650,215.

permeable to liquid oxygen. The combustible substance forming the body of the cartridge is preferably of lamp black, and is retained in the inner envelope and prior to use this inner envelope need not be placed in the outer one. In use, the cartridge with its inner envelope is dipped or dropped into the liquid oxygen, and when the lamp black becomes thoroughly saturated with the liquid oxygen the cartridge is withdrawn and is placed in the outer envelo e or container, and the latter is closed y loosely twisting together the paper walls at the end. The cart-ridge is then placed in the desired position for blasting, and is lighted in any suitable manner commonly used for cartridges of this general type. The outer non-permeable envelope holds a jacket of ver cold gaseous oxygen around the inner jac et, and thus protects the inner jacket from direct absorption of heat from the body which is to be blasted. This cold oxygen jacket so retards the evaporation of the liquid oxygen from the inner container that the cartridge will retain the full amount of oxygen required for a powerful explosion for a very considerable period of time. This allows other cartridges to be placed in the hole, the fuse put inposition, the hole closed, and the men to reach a point of safety before there is any appreciable deterioration of the efliciency of the cartridge. The outer envelope being closed merely by a loose twisting together of the walls at the end, permits the escape of oxygen without bursting the outer container prior to the explosion.

In order to retaina maximum amount of oxygen at the innermost portion of the cartridge, I preferably thread lengthwise through the center of the latter a piece of loose woven cotton cord or lamp wick which has free spaces between the fibers thereof. After the lamp black has been packed in the inner envelope and the latter has been closed, the lamp wick may be threaded lengthwise through the cartridge by the use of a long needle, and the ends then cut off so that they. extend slightly beyond the cartridge at each end of the latter. As the cartridge is dipped into the liquid oxygen the latter may flpw in along this center wicking at a rapid rate, and when the saturation has been effected there will be a larger proportionate amount of liquid within the wicking than in the lamp black forming the body portion of the cartridge. Thisexcess of oxygen serves for the combustion of the Wicking itself at the instant of explosion, and also serves as a reservo1r to replenish the oxygen in the lamp black or body portion to make up for evaporation from the latter.

I do not wish to be limited to any specific form of envelopes or containers, and therefore the construction shown in the accompanying drawing is to be considered in an illustrative rather than in a lim1t1ng sense. In these drawings:

Fig. 1 is a central longitudinal section through a cartridge having only the inner envelope or container.

Fig. 2 is a perspective view of the outer envelope or container, and

Fig. 3 is a longitudinal section of the complete cartridge when ready for 1gn1t1on.

In the construction illustrated, the inner container is in the form of a paper bag 10 which may be of any desired cross-sectlonal form, but preferably rather small in diam'eter in respect to its length. This filled with lamp black 11, and the open end of the bag is then twisted together and forced down into the body of the lamp black to form a closed end 12. This cartridge may have a center wicking 13 threaded lengthwise through the same after it has been completed. The ends of this wicking may project beyond the ends of the inner envelope. In" connection with this cartridge there is provided an outer envelope 14, as shown in Fig. 2. This may be a simple bag slightly larger in dimension than the inner bag 10, but it is made of such material as is not readily permeable by liquid oxygen. The inner bag may be made of ordinary unglazed paper, while the outer bag is preferably made of paraffin-coated paper. The difference in size of the bags is such that the cartridge having the inner envelope or container may be readily dropped into the outer envelope I or container after being withdrawn from the liquid oxygen. As soon as thesaturated cartridge is placed in the outer envelope the open end of the latter is closed by twisting the walls together. This will permit of the escape through the creases at the twisted end of a small amount of oxygen, and prevent undue pressure in the outer envelope, but will retain in the outer en:

velope an insulating layer of the extremely cold gaseous oxygen resulting from the evaporation from the inner envelope. As previously noted the inner envelo e may be inserted in the outer envelope or the first time after the dipping or saturating operation. In other words, the cartridge may be shipped and stored with only a single en- .air. centrally disposed wick orcarrier for the velope, and the outer envelop es separately manufactured and shipped to the point of use. Q 1

So far as my invention involves the use of an outer envelope into which the saturated cartridge is placed, it will be evident that it is not dependent upon the use of any. specific material as the combustible substance forming the body of the cartridge, nor is it dependent upon any specific form of the cartridge part which is dipped or saturated in the liquid oxygen or liquid So far as my invention involves the liquid oxygen, it will be apparent that a cartridge embodying this feature may be used without placing in an outer envelope.

In referring to the combustion supporting substance as liquid oxygen, I wish to include not only liquid oxygen but substances containing liquid oxygen, such as liquid air, and also include other liquefied gases adapted for the same purpose.

Having thus described my invent-ion, what I claim as new and desire to secure by Let-.

ters Patent is: I

1. In blasting, the process steps comprising dipping a body of finely subdivided combustible material in liquid oxygen to saturate said body, placing the saturated body in a loose fitting outer container substantially non-permeable to liquid oxygen to thereby retain about said body a jacket of cold gaseous oxygen, and placing the saturated body and container in the body to be blasted.

2. In blasting, the process steps comprising dipping a body of finely subdivided combustible material in liquid oxygen to saturate said body, placing the saturated body in a loose fittin outer container substantially non-.permeafiile to liquid oxygen, closing the container to prevent the escape of liquid but permit escape of oxygen gas to thereby retain about said body a 'acket of cold gaseous oxygen, and placing t esaturated-bodfy and container in the body to be blasted.

3. The process of preparing a blasting cartridge which consists in saturating a body of finely subdivided combustible material withliquid oxygen, placing the saturated body in a loose fitting outer container of combustible material but substantially non-permeable to liquid oxygen, and closing the container to prevent the escape of liquid oxygen but permit the escape of gaseous oxygen.

4. A cartridge including a body of combustible materlal adapted to be saturated with liquid oxygen, and an outer detachable loose fitting container substantiallynon-per- "meable to liquid oxygen but-having an outlet for gaseous oxygen and adapted to reuration of the latter.

5. A cartridge including-a paper bag filled with a finely subdivided combustible substance, said bag being permeable to liquid oxygen, and a separate loose fitting outer bag into which the inner Jag may be placed after the saturating operation, the outer bag having its walls substantially non-permeable to liquidoxygen.

6. A cartridge including an inner container filled with a finely subdivided combustible material and ermeable to permit the saturation of said ody with liquid oxygen when the container with its filler is dipped in liquid oxygen, and an outer container substantially non-permeable to liquid oxygen and of larger size than the inner container to receive the latter after the saturation and to form with the latter spaced walls for retaining a jacket of cold gaseous oxygen about the inner container.

7. A blasting cartridge including a paper bag filled with finely subdivided combustible material, an outer bag of parafiin coated paper, the outer bag being larger than the inner bag to provide a loose fit, and ofgreater length to permit the outer bag to be closed by twisting the walls together.

8. A cartridge including a container filled with a body of finely subdivided combustible material, and a filamentary member extending lengthwise through the container and having larger spaces between the filaments thereof than those between the particles of said body to form an inner reservoir for liquid oxygen. 1

cartridge including a container, a body of finely subdivided combustible material therein, and -a loosely woven combustible wicking extending through the walls of the container and through said body and adapted to conduct liquid oxygen to the interior of the cartridge When the entire container is dipped into the liquid oxygen.

opposite ends extending through the walls of said container and adapted to conduct liquid oxygen to the interior of the cartridge when the entire container is dipped into the liquid oxygen. 5

Signed at New York in the county of New York and State of New York this fifth day of July A. D. 1923'.

p GEORGE CHARLES LEWIS. 

